Folding-up mechanism for an electric treadmill

ABSTRACT

A folding-up mechanism for an electric treadmill having a single lifting motor for adjusting a platform frame to an inclined and upright position with a handrail frame moved to a storage position. The lifting motor and a drive screw are interposed between two base frames. The drive screw is screwed in a slip pipe with female thread. An intermediate tube is pivotally coupled to a rear end of the slip pipe with a front crossbar and a handrail frame coupled to the opposing end of the intermediate tube. One end of the platform frame is pivotally attached to an upright bar of the base frames while a bottom side of the platform frame is pivotally coupled to a telescopic tube, a pull rod, and a push rod that are in turn coupled to the slip pipe, the intermediate tube, and the handrail frame so that the slip pipe is movable to and fro when the lifting motor is activated to impart an in-place rotation to the drive screw, thereby achieving the expected effects.

This application is a continuation-in-part of U.S. patent application ofSer. No. 11/123,159 filed May 6, 2005.

BACKGROUND OF THE INVENTION

1. Fields of the Invention

The invention relates to a folding-up mechanism for an electrictreadmill, and more particularly, to a folding-up mechanism having asingle lifting motor for adjusting a platform frame to an inclined andupright position with a handrail frame moved to a storage position.

2. Description of the Related Art

A tilting mechanism of a conventional treadmill is used to adjust thesupported angle of a main frame relative to a base frame for creating acertain walking slope. Meanwhile, a fold-up mechanism is used to fold-upthe main frame in a storage position for reducing the space occupied bythe treadmill. Generally speaking, these can be classified into a manualand an automatic type. The present invention is an improvement of theabove-mentioned mechanisms.

U.S. Pat. No. 5,733,228 teaches a mechanism with a lifting motor, pullcable, pulley wheels and return springs to fold-up a main frame of atreadmill between two handrails. Therefore, the main frame can be liftedin a tilt and a fold-up position. Although this prior art has itsoriginal design, the mechanism requires complicated and miscellaneouscomponents. In addition, the pull cable and the return springs aresubject to fatigue and slack. This is regarded as drawbacks of thisprior art.

Another prior art U.S. Pat. No. 6,325,745 teaches a treadmill with itsmain frame pivotally coupled to a slide groove of a base. Meanwhile, alifting motor pushes downwardly a supporting rod pivotally attached tothe main frame. In this way, the main frame is swivelable in the slidegroove to be lifted in a storage position. However, this apparatusdoesn't have the function to bring the main frame in a tilt position.Besides, the lifting motor applied its driving force to only one end ofthe main frame so that the arm of force is evidently mechanically tooshort. Especially, the lifting motor is movable with the lifting action,and the lifting motor bears all loading created by the main frame. So,the lifting motor is subject to overload that would cause damage to thelifting motor.

A further prior art U.S. Pat. No. 6,015,368 teaches a treadmill with alonger spindle and sleeve to support a rear supporting rod at a bottomend behind a main frame over a long distance to fold-up the main frame.Also, this prior art doesn't have the function of tilting the mainframe. Moreover, a lifting motor has to be movable with the liftingaction. Thus, it has the same disadvantages as U.S. Pat. No. 6,325,745.

SUMMARY OF THE INVENTION

Thus, based on the above-mentioned considerations, the designer employsa flat lifting motor in cooperation with a drive screw, a slip pipe, anintermediate tube, a telescopic tube, a pull rod, a push rod, and ahandrail frame to allow a platform frame to swivel on a pivotal point ofan upright bar for adjusting the platform frame to an inclined andupright position with the handrail frame moved to a storage position. Inthis way, the lifting motor can complete the lifting action with lesstorque output so that the service life of the lifting motor can beextended. Moreover, the supporting force can be optimally controlled.This is the primary object of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accomplishment of this and other objects of the invention willbecome apparent from the following description and its accompanyingdrawings of which:

FIG. 1 is a perspective view of a preferred embodiment of the invention;

FIG. 2 is an axially cutaway view of the preferred embodiment of theinvention in accordance with FIG. 1; and

FIG. 3 is an axially cutaway view of the preferred embodiment of theinvention in accordance with FIG. 1, showing the action to bring aplatform frame in an inclined position;

FIG. 4 is an axially cutaway view of the preferred embodiment of theinvention in accordance with FIG. 1, showing the action to lift theplatform frame toward an upright position; and

FIG. 5 is an axially cutaway view of the preferred embodiment of theinvention in an upright position with a handrail frame to be moved in astorage position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, a treadmill in accordance with the inventionincludes:

a platform frame 10 having a rear roller 13 driven by a motor 11 througha driving belt 12, the rear roller 13 being active in cooperation with afront roller 14 for an in-place rotation of a continuous belt 15;

two base frames 20 having an upright bar 21 extending from a centralpoint thereof, the platform frame 10 being pivotally connected to theupright bars 21;

a lifting motor 30 for driving a drive screw 31 to undergo an in-placerotation;

a slip pipe 40 having a female threaded hole 41 for receiving the drivescrew 31;

an intermediate tube 50 pivotally disposed at a distal end of the slippipe 40, a front crossbar 51 being connected at an opposing end of theintermediate tube 50, a handrail frame 52 extending upwardly from a rearend of the intermediate tube 50, an electronic console 53 being fittedatop the handrail frame 52;

a telescopic tube 60 with both ends thereof pivotally coupled to a firstcrossbar 16 at a bottom side of the platform frame 10 and to a top sideof the rear end of the slip pipe 40, respectively;

a pull rod 70 with both ends thereof pivotally coupled to a secondcrossbar 17 at a bottom side of the platform frame 10 and to a middleportion of the intermediate tube 50, respectively; and

a push rod 90 with both ends thereof pivotally coupled to the read endof the slip pipe 40 and to a bottom end of the handrail frame 52,respectively.

Referring to FIGS. 2 through 5, the action of the aforementionedconfiguration is shown. The slip pipe 40 is moved to and fro when thelifting motor 30 is activated to impart an in-place rotation to thedrive screw 31. As shown in FIGS. 2 und 3, the platform frame 10 isadjusted to an inclined position. At this point, the platform frame 10is swiveled on a pivotal point A of the upright bar 21 for simulating anuphill or a flat surface. As shown in FIGS. 4 und 5, the platform frame10 is adjusted to an upright storage position. Referring to FIG. 3, asleeve 61 reaches the end of the telescopic tube 60. When the slip pipe40 continues to move toward the lifting motor 30, the telescopic tube 60will gradually lift the platform frame 10 due to the connectionrelationship. Since the intermediate tube 50 and the slip pipe 40 arepivotally coupled, the intermediate tube 50 can be swiveled on a pivotalpoint B to be lifted by the pull rod 70 until the platform frame 10 ismoved to an upright position. When the intermediate tube 50 is movedupwardly, the distance between the pivotal point C and the pivotal pointB is reduced. Under the condition that the length of the push rod 90remains unchanged, the handrail frame 52 will be moved toward theplatform frame 10.

In order to bring the main frame 10 in operational position, the slidetube 40 is extended by the lifting motor 30 in a reverse drivedirection.

In light of the safety, a protection cover 22 is accurately extendedbetween both inverted T-bases 20 to prevent the internal transmissionunits from direct exposure to the outside.

In order to separate the tilting action from the fold-up action as wellas to prevent the lifting motor 30 from over-driving, a sensing switch80 is mounted at a proper place of the traveling path of the telescopicunit 60 or the slide tube 40. Accordingly, the tilting action from thefold-up action can be effectively controlled by contact or release ofthe sensing switch 80.

A simple example will be described to detail the action of the sensingswitch 80 as follows:

When any sensing switch 80 is touched during the operation of the motor11 and the continuous moving belt 15, it is programmed that the mainframe 10 is located at a highest point of the tilting action so that nomore lifting action is permitted. In this way, the lifting motor 30 canbe only operated in a reverse manner to lower the tiling angle of themain frame 10 relative to the inverted T-bases 20. Besides, the sensingswitch 80 is inoperative when the continuous moving belt 15 is out ofoperation. This results in a better safety in use.

The telescopic unit 60 can be replaced by a pneumatic, a hydrauliccylinder (not shown) or other equivalent units for both enhancing thelifting effect and reducing the loading of the lifting motor 30.

Many changes and modifications in the above-described embodiment of theinvention can, of course, be carried out without departing from thescope thereof. Accordingly, to promote the progress in science and theuseful arts, the invention is disclosed and is intended to be limitedonly by the scope of the appended claims.

1. A folding-up mechanism for an electric treadmill comprising: a) aplatform frame having a rear roller driven by a motor through a drivingbelt, the rear roller being active in cooperation with a front rollerfor an in-place rotation of a continuous belt; b) two base frames eachhaving an upright bar extending from a central point thereof, theplatform frame being pivotally connected to the upright bars; c) alifting motor for driving a drive screw to undergo an in-place rotation;d) a slip pipe having a female threaded hole for receiving the drivescrew; e) an intermediate tube pivotally disposed at a distal end of theslip pipe, a front crossbar being connected at an opposing end of theintermediate tube, a handrail frame extending upwardly from a rear endof the intermediate tube, an electronic console being fitted atop thehandrail frame; f) a telescopic tube with both ends thereof pivotallycoupled to a first crossbar at a bottom side of the platform frame andto a top side of the rear end of the slip pipe, respectively; g) a pullrod with both ends thereof pivotally coupled to a second crossbar at abottom side of the platform frame and to a middle portion of theintermediate tube, respectively; and h) a push rod with both endsthereof pivotally coupled to the read end of the slip pipe 40 and to abottom end of the handrail frame, respectively. wherein the slip pipe ismovable to and fro when the lifting motor is activated to impart anin-place rotation to the drive screw, thereby bringing the platformframe in an inclined or upright position with the handrail frame movedto a storage position.
 2. The fold-up mechanism for an electrictreadmill as claimed in claim 1 wherein a sensing switch is mounted on atraveling path of the telescopic unit and the slide tube.
 3. The fold-upmechanism for an electric treadmill as claimed in claim 1 wherein thetelescopic unit includes a pneumatic cylinder.
 4. The fold-up mechanismfor an electric treadmill as claimed in claim 1 wherein the telescopicunit includes a hydraulic cylinder.
 5. A folding-up mechanism for anelectric treadmill having a single lifting motor for adjusting aplatform frame to an inclined and upright position with a handrail framemoved to a storage position, wherein the lifting motor and a drive screware interposed between two base frames; wherein the drive screw isscrewed in a slip pipe with female thread; wherein an intermediate tubeis pivotally coupled to a rear end of the slip pipe with a frontcrossbar and a handrail frame coupled to the opposing end of theintermediate tube; and wherein one end of the platform frame ispivotally attached to an upright bar of the base frames while a bottomside of the platform frame is pivotally coupled to a telescopic tube, apull rod, and a push rod that are in turn coupled to the slip pipe, theintermediate tube, and the handrail frame, so that the slip pipe ismovable to and fro when the lifting motor is activated to impart anin-place rotation to the drive screw, thereby achieving the expectedeffects.
 6. The fold-up mechanism for an electric treadmill as claimedin claim 5 wherein a sensing switch is mounted on a traveling path ofthe telescopic unit and the slide tube.
 7. The fold-up mechanism for anelectric treadmill as claimed in claim 5 wherein the telescopic unitincludes a pneumatic cylinder.
 8. The fold-up mechanism for an electrictreadmill as claimed in claim 5 wherein the telescopic unit includes ahydraulic cylinder.